黄鳍鲷仔、稚、幼鱼消化道形态组织学观察

[目的]了解黄鳍鲷(Sparus latus)仔、稚、幼鱼消化道的形态组织学特征,为其发育生物学研究和鱼苗健康繁育提供理论依据,进一步充实黄鳍鲷生物学研究文库.[方法]采用常规石蜡组织切片的方法,对黄鳍鲷仔、稚、幼鱼消化道的形态组织进行观察.[结果]2日龄仔鱼消化道仅为一条未分化的管道;5日龄仔鱼消化道分化为食道、胃和肠道,食道黏膜上皮由立方状细胞组成,胃黏膜上皮由单层矮柱状细胞组成,二者均无黏膜褶皱,肠分化为小肠和直肠,小肠壁内部出现黏膜褶皱,直肠内壁无褶皱;7日龄仔鱼消化道进一步分化,各段管壁增厚,食道和胃内壁仍无黏膜褶皱,幽门盲囊开始分化,小肠黏膜上皮中含有大量杯状细胞.稚鱼消化道在质方面向幼鱼的基本型发育,食道、胃、幽门盲囊、肠道表现出固有的类型和数量,消化道扩张,肌肉层加厚,黏膜褶皱加深,杯状细胞增多.幼鱼消化道进一步发育完善,其组织结构与成鱼相似,由食道、胃、幽门盲囊、小肠和直肠组成;各部分管壁从内到外都分化为黏膜层、黏膜下层、肌肉层和浆膜层.[结论]黄鳍鲷消化道的胚后发育特征与其摄食方式及功能相适应,进一步证实无论鱼类处于生长发育的任何阶段,其消化道形态组织结构均与功能密切相关.

Histomorphology observation on digestive tract of larva, juvenile and young yellowfin black porgy (Sparus latus)

[Objective]The present experiment was aimed to understand the morphological and histological characteristics of digestive tract of larvae, juvenile and young yellowfin black porgy (Sparus latus) to provide references for development biology research and fry healthy breeding to further enrich the database of yellowfin black porgy biology. [Method]Conventional paraffin tissue section was used to observe the morphology and histology of digestive tract of larvae, juvenile, and young yellowfin black porgy. [Result]The digestive tract of two-day-old larva was an undifferentiated canal. The digestive tract of five-day-old larva was divided into esophagus, stomach, and intestinal tract. The esophagus epithelium was made up with cubic cells, and the epithelium of stomach consisted of single low columnar cells, neither of which had mucosal fold. The intestines were differentiated in the small intestine and rectum. The small intenstine wall had mucosal wrinkles, but the rectum had not. The digestive tract of seven-day-old old larva showed further differences with thicker walls and without mucosal wrinkles in esophagus and stomach. The pyloric caeca also began to differentiate, and the goblet cells in small intestine were abundant. The digestive canal of juvenile grew into young qualitatively. Esophagus, stomach, pyloric caecum and intestinal tract exhibit innate types and fixed numbers. The digestive tract was expanded, muscularis was extruded, mucosal wrinkles deepened, and goblet cells were increased. The digestive tract of young yellowfin black porgy developed more and had similar histology structure to adult, composed of esophagus, stomach, pyloric caeca, small intenstine, and rectum; the wall of each part differentiated into mucous membrane, submucosa, muscularis, and serous membrane from the inside to outside. [Conclusion]Post-embryonic development characteristics of digestive tract in yellowfin black porgy coincided with the ingestive way of yellowfin black porgy and the function of digestive tract, which further proves that regardless of growth stage, morphology and histology of digestive tract were closely related to its function.